SOLUTION: Hey! First of all, thanks for taking the time to read this! Another math student needs help! Let's say Mike has four types of stamps, with a total of 80 stamps. He has some 29 c

Question 525672: Hey! First of all, thanks for taking the time to read this! Another math student needs help!
Let's say Mike has four types of stamps, with a total of 80 stamps. He has some 29 cent stamps, some 32 cent stamps, some 3 cent stamps, and some 19 cent stamps.
The stamps have a total value of $14.94. There are 32 stamps that are worth more than 25 cents. Four times the number of 29 cent stamps minus twice the number of 3 cent stamps is 6. How many of each type of stamp does Mike have?
All I need is the set up matrix equation, but you can go further if you want. Thank you!
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Let's say Mike has four types of stamps, with a total of 80 stamps.
Quantity Eq: a + b +c + d = 80
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He has some 29 cent stamps, some 32 cent stamps, some 3 cent stamps, and some 19 cent stamps. The stamps have a total value of $14.94.
Value Eq: 29a + 32b + 3c + 19d = 1494 cents
---------------------------------
There are 32 stamps that are worth more than 25 cents
a + b = 32
------------------------
Four times the number of 29 cent stamps minus
twice the number of 3 cent stamps is 6.
4a - 2c = 6
------------------------
How many of each type of stamp does Mike have?
All I need is the set up matrix equation
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Cheers,
Stan H.
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